loslib.c
(5.4.7)
/*
** $Id: loslib.c $
** Standard Operating System library
** See Copyright Notice in lua.h
*/
#define loslib_c
#define LUA_LIB
#include "lprefix.h"
#include <errno.h>
#include <locale.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include "lua.h"
#include "lauxlib.h"
#include "lualib.h"
/*
** {==================================================================
** List of valid conversion specifiers for the 'strftime' function;
** options are grouped by length; group of length 2 start with '||'.
** ===================================================================
*/
#if !defined(LUA_STRFTIMEOPTIONS) /* { */
#if defined(LUA_USE_WINDOWS)
#define LUA_STRFTIMEOPTIONS "aAbBcdHIjmMpSUwWxXyYzZ%" \
"||" "#c#x#d#H#I#j#m#M#S#U#w#W#y#Y" /* two-char options */
#elif defined(LUA_USE_C89) /* ANSI C 89 (only 1-char options) */
#define LUA_STRFTIMEOPTIONS "aAbBcdHIjmMpSUwWxXyYZ%"
#else /* C99 specification */
#define LUA_STRFTIMEOPTIONS "aAbBcCdDeFgGhHIjmMnprRStTuUVwWxXyYzZ%" \
"||" "EcECExEXEyEY" "OdOeOHOIOmOMOSOuOUOVOwOWOy" /* two-char options */
#endif
#endif /* } */
/* }================================================================== */
/*
** {==================================================================
** Configuration for time-related stuff
** ===================================================================
*/
/*
** type to represent time_t in Lua
*/
#if !defined(LUA_NUMTIME) /* { */
#define l_timet lua_Integer
#define l_pushtime(L,t) lua_pushinteger(L,(lua_Integer)(t))
#define l_gettime(L,arg) luaL_checkinteger(L, arg)
#else /* }{ */
#define l_timet lua_Number
#define l_pushtime(L,t) lua_pushnumber(L,(lua_Number)(t))
#define l_gettime(L,arg) luaL_checknumber(L, arg)
#endif /* } */
#if !defined(l_gmtime) /* { */
/*
** By default, Lua uses gmtime/localtime, except when POSIX is available,
** where it uses gmtime_r/localtime_r
*/
#if defined(LUA_USE_POSIX) /* { */
#define l_gmtime(t,r) gmtime_r(t,r)
#define l_localtime(t,r) localtime_r(t,r)
#else /* }{ */
/* ISO C definitions */
#define l_gmtime(t,r) ((void)(r)->tm_sec, gmtime(t))
#define l_localtime(t,r) ((void)(r)->tm_sec, localtime(t))
#endif /* } */
#endif /* } */
/* }================================================================== */
/*
** {==================================================================
** Configuration for 'tmpnam':
** By default, Lua uses tmpnam except when POSIX is available, where
** it uses mkstemp.
** ===================================================================
*/
#if !defined(lua_tmpnam) /* { */
#if defined(LUA_USE_POSIX) /* { */
#include <unistd.h>
#define LUA_TMPNAMBUFSIZE 32
#if !defined(LUA_TMPNAMTEMPLATE)
#define LUA_TMPNAMTEMPLATE "/tmp/lua_XXXXXX"
#endif
#define lua_tmpnam(b,e) { \
strcpy(b, LUA_TMPNAMTEMPLATE); \
e = mkstemp(b); \
if (e != -1) close(e); \
e = (e == -1); }
#else /* }{ */
/* ISO C definitions */
#define LUA_TMPNAMBUFSIZE L_tmpnam
#define lua_tmpnam(b,e) { e = (tmpnam(b) == NULL); }
#endif /* } */
#endif /* } */
/* }================================================================== */
#if !defined(l_system)
#if defined(LUA_USE_IOS)
/* Despite claiming to be ISO C, iOS does not implement 'system'. */
#define l_system(cmd) ((cmd) == NULL ? 0 : -1)
#else
#define l_system(cmd) system(cmd) /* default definition */
#endif
#endif
static int os_execute (lua_State *L) {
const char *cmd = luaL_optstring(L, 1, NULL);
int stat;
errno = 0;
stat = l_system(cmd);
if (cmd != NULL)
return luaL_execresult(L, stat);
else {
lua_pushboolean(L, stat); /* true if there is a shell */
return 1;
}
}
static int os_remove (lua_State *L) {
const char *filename = luaL_checkstring(L, 1);
errno = 0;
return luaL_fileresult(L, remove(filename) == 0, filename);
}
static int os_rename (lua_State *L) {
const char *fromname = luaL_checkstring(L, 1);
const char *toname = luaL_checkstring(L, 2);
errno = 0;
return luaL_fileresult(L, rename(fromname, toname) == 0, NULL);
}
static int os_tmpname (lua_State *L) {
char buff[LUA_TMPNAMBUFSIZE];
int err;
lua_tmpnam(buff, err);
if (l_unlikely(err))
return luaL_error(L, "unable to generate a unique filename");
lua_pushstring(L, buff);
return 1;
}
static int os_getenv (lua_State *L) {
lua_pushstring(L, getenv(luaL_checkstring(L, 1))); /* if NULL push nil */
return 1;
}
static int os_clock (lua_State *L) {
lua_pushnumber(L, ((lua_Number)clock())/(lua_Number)CLOCKS_PER_SEC);
return 1;
}
/*
** {======================================================
** Time/Date operations
** { year=%Y, month=%m, day=%d, hour=%H, min=%M, sec=%S,
** wday=%w+1, yday=%j, isdst=? }
** =======================================================
*/
/*
** About the overflow check: an overflow cannot occur when time
** is represented by a lua_Integer, because either lua_Integer is
** large enough to represent all int fields or it is not large enough
** to represent a time that cause a field to overflow. However, if
** times are represented as doubles and lua_Integer is int, then the
** time 0x1.e1853b0d184f6p+55 would cause an overflow when adding 1900
** to compute the year.
*/
static void setfield (lua_State *L, const char *key, int value, int delta) {
#if (defined(LUA_NUMTIME) && LUA_MAXINTEGER <= INT_MAX)
if (l_unlikely(value > LUA_MAXINTEGER - delta))
luaL_error(L, "field '%s' is out-of-bound", key);
#endif
lua_pushinteger(L, (lua_Integer)value + delta);
lua_setfield(L, -2, key);
}
static void setboolfield (lua_State *L, const char *key, int value) {
if (value < 0) /* undefined? */
return; /* does not set field */
lua_pushboolean(L, value);
lua_setfield(L, -2, key);
}
/*
** Set all fields from structure 'tm' in the table on top of the stack
*/
static void setallfields (lua_State *L, struct tm *stm) {
setfield(L, "year", stm->tm_year, 1900);
setfield(L, "month", stm->tm_mon, 1);
setfield(L, "day", stm->tm_mday, 0);
setfield(L, "hour", stm->tm_hour, 0);
setfield(L, "min", stm->tm_min, 0);
setfield(L, "sec", stm->tm_sec, 0);
setfield(L, "yday", stm->tm_yday, 1);
setfield(L, "wday", stm->tm_wday, 1);
setboolfield(L, "isdst", stm->tm_isdst);
}
static int getboolfield (lua_State *L, const char *key) {
int res;
res = (lua_getfield(L, -1, key) == LUA_TNIL) ? -1 : lua_toboolean(L, -1);
lua_pop(L, 1);
return res;
}
static int getfield (lua_State *L, const char *key, int d, int delta) {
int isnum;
int t = lua_getfield(L, -1, key); /* get field and its type */
lua_Integer res = lua_tointegerx(L, -1, &isnum);
if (!isnum) { /* field is not an integer? */
if (l_unlikely(t != LUA_TNIL)) /* some other value? */
return luaL_error(L, "field '%s' is not an integer", key);
else if (l_unlikely(d < 0)) /* absent field; no default? */
return luaL_error(L, "field '%s' missing in date table", key);
res = d;
}
else {
if (!(res >= 0 ? res - delta <= INT_MAX : INT_MIN + delta <= res))
return luaL_error(L, "field '%s' is out-of-bound", key);
res -= delta;
}
lua_pop(L, 1);
return (int)res;
}
static const char *checkoption (lua_State *L, const char *conv,
ptrdiff_t convlen, char *buff) {
const char *option = LUA_STRFTIMEOPTIONS;
int oplen = 1; /* length of options being checked */
for (; *option != '\0' && oplen <= convlen; option += oplen) {
if (*option == '|') /* next block? */
oplen++; /* will check options with next length (+1) */
else if (memcmp(conv, option, oplen) == 0) { /* match? */
memcpy(buff, conv, oplen); /* copy valid option to buffer */
buff[oplen] = '\0';
return conv + oplen; /* return next item */
}
}
luaL_argerror(L, 1,
lua_pushfstring(L, "invalid conversion specifier '%%%s'", conv));
return conv; /* to avoid warnings */
}
static time_t l_checktime (lua_State *L, int arg) {
l_timet t = l_gettime(L, arg);
luaL_argcheck(L, (time_t)t == t, arg, "time out-of-bounds");
return (time_t)t;
}
/* maximum size for an individual 'strftime' item */
#define SIZETIMEFMT 250
static int os_date (lua_State *L) {
size_t slen;
const char *s = luaL_optlstring(L, 1, "%c", &slen);
time_t t = luaL_opt(L, l_checktime, 2, time(NULL));
const char *se = s + slen; /* 's' end */
struct tm tmr, *stm;
if (*s == '!') { /* UTC? */
stm = l_gmtime(&t, &tmr);
s++; /* skip '!' */
}
else
stm = l_localtime(&t, &tmr);
if (stm == NULL) /* invalid date? */
return luaL_error(L,
"date result cannot be represented in this installation");
if (strcmp(s, "*t") == 0) {
lua_createtable(L, 0, 9); /* 9 = number of fields */
setallfields(L, stm);
}
else {
char cc[4]; /* buffer for individual conversion specifiers */
luaL_Buffer b;
cc[0] = '%';
luaL_buffinit(L, &b);
while (s < se) {
if (*s != '%') /* not a conversion specifier? */
luaL_addchar(&b, *s++);
else {
size_t reslen;
char *buff = luaL_prepbuffsize(&b, SIZETIMEFMT);
s++; /* skip '%' */
s = checkoption(L, s, se - s, cc + 1); /* copy specifier to 'cc' */
reslen = strftime(buff, SIZETIMEFMT, cc, stm);
luaL_addsize(&b, reslen);
}
}
luaL_pushresult(&b);
}
return 1;
}
static int os_time (lua_State *L) {
time_t t;
if (lua_isnoneornil(L, 1)) /* called without args? */
t = time(NULL); /* get current time */
else {
struct tm ts;
luaL_checktype(L, 1, LUA_TTABLE);
lua_settop(L, 1); /* make sure table is at the top */
ts.tm_year = getfield(L, "year", -1, 1900);
ts.tm_mon = getfield(L, "month", -1, 1);
ts.tm_mday = getfield(L, "day", -1, 0);
ts.tm_hour = getfield(L, "hour", 12, 0);
ts.tm_min = getfield(L, "min", 0, 0);
ts.tm_sec = getfield(L, "sec", 0, 0);
ts.tm_isdst = getboolfield(L, "isdst");
t = mktime(&ts);
setallfields(L, &ts); /* update fields with normalized values */
}
if (t != (time_t)(l_timet)t || t == (time_t)(-1))
return luaL_error(L,
"time result cannot be represented in this installation");
l_pushtime(L, t);
return 1;
}
static int os_difftime (lua_State *L) {
time_t t1 = l_checktime(L, 1);
time_t t2 = l_checktime(L, 2);
lua_pushnumber(L, (lua_Number)difftime(t1, t2));
return 1;
}
/* }====================================================== */
static int os_setlocale (lua_State *L) {
static const int cat[] = {LC_ALL, LC_COLLATE, LC_CTYPE, LC_MONETARY,
LC_NUMERIC, LC_TIME};
static const char *const catnames[] = {"all", "collate", "ctype", "monetary",
"numeric", "time", NULL};
const char *l = luaL_optstring(L, 1, NULL);
int op = luaL_checkoption(L, 2, "all", catnames);
lua_pushstring(L, setlocale(cat[op], l));
return 1;
}
static int os_exit (lua_State *L) {
int status;
if (lua_isboolean(L, 1))
status = (lua_toboolean(L, 1) ? EXIT_SUCCESS : EXIT_FAILURE);
else
status = (int)luaL_optinteger(L, 1, EXIT_SUCCESS);
if (lua_toboolean(L, 2))
lua_close(L);
if (L) exit(status); /* 'if' to avoid warnings for unreachable 'return' */
return 0;
}
static const luaL_Reg syslib[] = {
{"clock", os_clock},
{"date", os_date},
{"difftime", os_difftime},
{"execute", os_execute},
{"exit", os_exit},
{"getenv", os_getenv},
{"remove", os_remove},
{"rename", os_rename},
{"setlocale", os_setlocale},
{"time", os_time},
{"tmpname", os_tmpname},
{NULL, NULL}
};
/* }====================================================== */
LUAMOD_API int luaopen_os (lua_State *L) {
luaL_newlib(L, syslib);
return 1;
}